The present invention relates to a gravity-flow displacement beverage brewing apparatus, and more particularly, to a water flow control device within the brewing apparatus. The flow control device allows the user to control the brewing cycle initiation.
Small beverage brewers, such as residential coffee makers, produce a brewed beverage by transferring hot water from a reservoir to a brewing basket, which holds ingredients, such as coffee grinds, for brewing. The brewed beverage then flows into a carafe, and can be kept warm by a hotplate under the carafe.
One type of beverage brewer is the flash heating type of brewer apparatus. The flash heating brewer has a reservoir which is initially empty and to which the user can add cool water. The water is heated by heating coils within the reservoir, and the heated water is then transferred to the brewing basket. Because the heating process requires a finite period of time, the user has a window of time between the addition of the cool water to the apparatus and the flow of the brewed beverage into the carafe, during which the user can position a carafe beneath the brewing basket.
A second type of brewer, a gravity-flow displacement apparatus, has gained consumer popularity because this type of brewer delivers a hot beverage essentially immediately after the addition of cool water to the reservoir. In the displacement type of brewer, the reservoir holds heated water at all times. When the user adds cool water to the brewer, the cool water displaces the heated water in the reservoir forcing the heated water into the brewing basket. Because the cool water displaces preheated water, beverage brewing begins immediately upon addition of the cool water.
With the more rapid brewing of the displacement type brewer, however, there are certain attendant disadvantages. For example, the user may desire to use the same carafe to add cool water to the reservoir and to receive the brewed beverage. If the user does not replace the carafe under the brewing basket rapidly enough, the brewed beverage can spill onto the hotplate and surrounding area.
Various attempts have been made to provide the user with a window of time between the addition of the cool water and the transferring of the heated water to the brewing basket. For example, the brewer described in U.S. Pat. No. 5,251,541, assigned to Bunn-O-Matic, is a displacement-type brewer that has a stopper that can be positioned in a port between a fill basin, where the cool water initially enters the brewer, and a heated water reservoir. The stopper position is controlled by a rotatable lid that covers an opening in the top of the brewer that provides access to the fill basin. The stopper is attached to one end of a pivotally mounted lever, the motion of the lever being controlled by a fin mounted on a shaft attached to the lid. While solving the problem of prematurely initiating the brewing cycle, the structure of the lid and lever system is relatively complex, increasing the probability of malfunctions occurring with extended use.